Top definition
1. Basically, a kid posing as a bamf who stands behind his/her crew and is afraid to take real action in a fight.
2. Someone who claims they can kick ass, and they chicken out when someone wants to go.
James: I saw Jason behind those punks fighting after-school today. What a whimp.
Rob: I know, such a jack in the back.
by baddefinintionperson May 27, 2009
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